4. Earthquakes PT.1

• earthquake - a sudden shaking of the ground caused by the sudden release of energy
• focus - the point underground where an earthquake starts
• epicentre - the point on the earth's surface directly above the focus of an earthquake
• fault lines - cracks in the earth's crust that can cause earthquakes
• shockwaves - waves of energy that travel outwards from the point of an earthquake
• aftershocks - seismic waves that occur after an earthquake and are caused by the movement of the earth's crust
• seismograph - a device that records the vibrations of the ground caused by an earthquake
• tsunami - a series of large waves caused by a large earthquake